Patent GB-1499759-A (GB)
Title: Process for polyester synthetic fibre products
IPC: D06M101/16
Filed: 1975-05-12
Abstract: 1499759 Modifying polyester fibres TOYO BOSEKI KK 12 May 1975 [21 Aug 1974] 19924/75 Headings D1B and DIP A method of modifying polyester synthetic fibre products e.g. to provide hydrophilic, antistatic and antisoil redeposition properties, comprises (i) providing a treating liquor containing a polyester polyether block copolymer stabilised by a specified surface active agent, (ii) adding an agent which together with the surface active agent adjusts the aggregation initiating temperature of the liquor to be within the range 65-125C, and (iii) then raising the temperature of the liquor to at least 1C, preferably 1-25C higher than the aggregation initiating temperature thereby to exhaust the copolymer onto the fibre product, which is dipped into the liquor before step (ii), between steps (ii) and (iii) or after step (iii). The process may be carried out simultaneously with dyeing, bleaching and other finishing treatments. A disperse dye may be included in the copolymer dispersion. The surface active agent has a formula I where R is an alkyl, alkenvl or alkyl aryl group; R. is H or methyl; A is -SO 3 , -(CH 2 ) m  SO 3  or -PO 3m ; m is 2 or 3; m is H, ammonium, substituted ammonium, lower alkyl or alkali metal; n is an integer of 4-20, sulphated alkyl aryl polyethers being preferred. The aggregation temperature adjusting agent may be an acid, ester or salt, especially a latent acid salt. Specified are hydrochloric and sulphuric acid, glycol and glyceryl esters, lactones and sultones, and salts having a large salting-out effect e.g. ammonium sulphate, sodium sulphate, sodium acetate, ammonium chloride and sodium chloride. During the heating step the pH of the liquor is reduced and exhaustion occurs. The temperature is preferably elevated at a speed of less than 10C/ minute to a treating temperature in the range of 66-150C. The liquor may further contain a dyeing carrier e.g. a benzoate, an optionally chlorinated hydrocarbon or an aromatic ester. Alternatively the fibre product may be pretreated optionally at elevated temperature and pressure with the dyeing carrier. The block copolymer may be water-dispersible and prepared from terephthalic acid and/or isophthalic acid or 1 or more lower alkyl esters of these acids, a lower alkylene (2-10C) glycol and a polyalkylene glycol of molecular weight 600-12,000 or monoether thereof, the molar ratio of terephthalate to isophthalate units being 100:0 to 50:50 and the molar ratio of terephthalate plus isophthalate units to polyalkylene glycol units being in the range of 2-15:1. The treating liquor may contain one or more hydrophobic processing agents selected from dyestuffs, fluorescent brighteners, softening and smoothing agents, flame retardents, antibacterial agents, ultraviolet-absorbing agents and bleaching agents. The fibre products may be in the form of filaments, fibres, yarns, slivers, woven, non- woven or knitted fabrics made from polyethylene terephthalate, polyethylene terephthalate isophthalate, polyethylene terephthalate butylene terephthalate or polyethylene terephthalate parahydroxybenzoate or blends thereof with one or more natural, regenerated, semisynthetic or synthetic fibres other than the polyester fibres. Alternatively the polyester fibres may be modified e.g. by formation of micropores to improve the wash-fastness of the finish, or during the polycondensation and/ or spinning process to render the fibres dyeable with acid and/or basic dyestuffs, antistatic or flame retardant, or by graftcopolymerisation of vinyl monomers.